METHOD OF DIRECTION FINDING TO HYDROBIONTS AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 1996 - IPC

FIELD: underwater acoustic, hydrobiology. SUBSTANCE: invention may be used in fish-searching system for detection and direction finding to accumulations of fish and individual fish by signals of their vital activities. For increase of precision of direction finding and noise immunity method of direction finding consists in two-channel reception of hydroacoustic signals with their subsequent processing in each channel and determination of direction to hydrobionts by results of comparison of processed hydroacoustic signals. Processing of hydroacoustic signals is conducted by way of parallel spectral analysis in n frequency channels with subsequent performance of adaptive change of levels of signals in each frequency subchannel. After this converter signals are compared with threshold values, signals exceeding threshold are displayed. Direction to hydrobionts is determined with equality of readings of indicators of both channels. Device for implementation of method incorporates unit of spatially spaced receivers, two amplifiers, analog-to-digital converter, unit of threshold elements, register, two spectrum analyzers, four units measuring root-mean-square values of signals, unit of pair averaging of root-mean-square signals in like subchannels, unit determining minimal level of signals, unit determining weight factors, first and second units of controlled attenuators, unit determining average value of normed signals, unit setting thresholds, first and second units of threshold elements, first and second units of adders, first and second units of filters. EFFECT: increased precision of direction finding to accumulation of fish and increased noise immunity. 6 cl, 5 dwg